The prior art includes U.S. Pat. No. 8,490,723 issued to Heinzmann et al., for an Apparatus and Methods for Control of a Vehicle (the '723 patent). This patent discloses a device having self-balancing and a support or load platform that is movable relative to the wheels. It should be recognized that movement of the load platform relative to the wheels is performed (in this class of device) to achieve a desired shifting of the center of gravity of the load as the device accelerates in the fore or aft direction.
In the '723 patent, the movement of the load platform (or its equivalent) relative to the frame or platform to which the wheels are coupled is achieved with a controller, actuator and corresponding track system. In response to control signals, the actuator precisely positions the load platform along the track as the vehicle moves.
This arrangement, however, is disadvantageous for several reasons. One is that the controller, actuator, 10 batteries, and precise-position track assembly increase the complexity of the device and hence the likelihood of device malfunction. Another is that they add to the weight, bulk and cost of the device.
U.S. Pat. No. 8,271,185, issued to Doi for a Vehicle (the '185 patent) and U.S. Patent Application no. 2010/0168993, also to Doi, disclose a vehicle in which the position of a weight or counter-balance is moved to adjust the center of gravity of the load relative to the wheels. This requires a controller, actuator, battery, weight-movement mechanical linkage, and the weight itself. Similar to the '723 patent, these components disadvantageously add to the weight, cost and potential failure of the device.
Thus a need exists in a self-balancing vehicle with a 25 manner of moving or adjusting the center of gravity relative to the wheels that is simpler, less expensive, less likely to fail and/or easier to work with, among other needed attributes.